This section is intended to provide a background or context. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
Multiple users may share spectrum bandwidth using various techniques, such as spectrum sharing, authorized/licensed shared access, secondary access, dynamic spectrum access, cognitive radio, general authorized access, etc. for example. These techniques allow additional users to have access to more spectrum in order to increasing their own capacity and coverage. Access may be gained by buying the usage rights of that piece of spectrum from a higher priority, primary or incumbent user or via opportunistic access to unoccupied or unused spectrum.
In the US, a portion of the federal advanced wireless services (AWS) system spectrum will become available to cellular operators on an authorized shared access (ASA) basis. Under ASA, a secondary user will share the spectrum with the federal government (the primary or incumbent user) through authorization by the primary user. When an authorization is granted, the secondary user has exclusive use of the spectrum. However, the primary user has priority access and can reacquire the spectrum as needed.
As a result, mobile network operators may share a portion of spectrum (such as an uplink (UL) bandwidth (BW) for example) with government users. When the priority users need the spectrum, the mobile network operators will clear the shared spectrum. During clearing, the mobile network operators can transition users in the shared spectrum to another portion of the spectrum (such as a second UL BW for example).
What is needed is a technique to coordinate spectrum evacuation so that the evacuation can be done quickly and efficiently without overloading the new bandwidth.